This standard series, IEC 61162-400 and upwards, specifies a communication protocol for use in integrated ship control (ISC) systems. It also specifies an interface description language for use together with the protocol, a set of rules for the use of this language and a set of standard interfaces described in the language. Finally, it also provides a test plan of required documents for equipment using this standard. This part of IEC 61162 gives a general overview of the functionality of the protocol and provides definitions common to the other fragments of the standard.